Bicycle frame



FIG. 1 is a perspective view of a bicycle frame embodying the design;

FIG. 2 is a right side elevation view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a front elevation view thereof;

FIG. 5 is a rear elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The portions of the bicycle frame shown in broken lines form no part of the claimed design. 

CLAIM We claim the ornamental design for a bicycle frame, as shown and described. 